Do any of you have a schematic of the Burk ARC-16 ESI card? I have a couple of cards needing repair. One has distorted audio and the other will not answer incoming calls. A diagram would greatly help. Thanks.

I have 6 ARC-16 units in several of the stations I service. Our land lines on a three of them went away as the phone companies didn't want to replace a major cable in the rural areas that deteriorated. We switched three xmttr sites to cell and the problems stayed with us. The ARC-16 ESI card does not recognize the tones when going thru cell systems. The Burk answers, plays the message and upon entering the password, immediately hangs up. We get highly distorted tones thru the cell system. Their filtering alters those tones and the Burk barfs! If you are trying to use the Burk via cell service, you are probably not going to have any success.

Our next effort is to try the SINE System. There are component changes listed in service bulletins that might allow us to use it. Will report on that effort when I get the SINE to play with.

Have two sites using a "home phone" cell unit and a Sine with success. These are Verizon cell phones with a telephone jack and external antenna. Interestingly, the A.T. & T version doesn't work--Sine won't answer.

If the ESI will not answer incoming calls, but is otherwise working (calls out OK), the ring detect optoisolator may be bad. On the older boards this is a 4N35, socketed and pretty easy to find and replace.

I had a Burk remote control at one site that developed distorted audio on phone calls. Turned out the R/C was fine, problem was with the lightning protection device on the phone line ahead of the Burk.

W4cl I could use both pdf schematics if you would email them to larrymilliken94@gmail.com I would appreciate it. And thanks awsherrill for the tip about the optoisolator! Thanks everyone for the help. As you know Burk no longer supports these remote control units.